Preselected stop means for tuner elements



Oct. 1-8; 1949.

o. E; WAGENKNECHT PRESELECTED STOP MEANS FOR'TUNER ELEMENTS 8Sheets-Sheet 1 Filed Dec. 51, 1943 0110 E. WAGENKNECHT INVENTOR. BYWWH/s AGENT Oct. 18, 1949. r E o. E. WAGENKNECHT 2,485,223

' PRESELECTED STOP MEANS Eon TUNER ELEMENTS Filed Dec. 31, 1943 8Sheets-Sheet 2 I l I FIG. l

OTTO E. WAGEN'KNEVOH T mvewron ll/S AGENT Oct. 18, 1949. i 0.1:.WAGENKNECHT 8 PRESELECT'ED STOP mmmsron TUNER'ELEMENTS Filed Dec. 51.194:: a Sheets-Sheet: s

OTTO E. WAGENKNECHT I INVENTOI? "maxim HIS AGE/V T Oct. 18,1949. 0. EWAGENKNECHT PRESELECTED STOP MEANS FOR TUNER ELEMENTS Filed Dec. 31,1943 4 8 Sheets-Sheet 4 OTTO E. WAGE NKNECHT INVENTOR.

HIS AGENT Oct. 18, 1949. o. E. WAGE NKNECHT v 2,485,223

. PRESELECTED STOP MEANS FOR TUNER ELEMENTS Filed Dec. 31, 1 94:s8Sheets-Sheet s HIS AGENT I 22s BYW Z I Oct, 18, 1949.

PRESELEC'I'ED STOP MEANS FOR TUNER ELEMENTS Filed Dec. 31, 1943 8Sheets-Sheet 7 FiG. l6

Ono E. WAGENKNECHT INVENTOR.

HIS AGENT F I 5. I?

o. E. WAGE KNECm 2,485,223

Oct. 18, 1949.

8 Sheets-Sheet 8 Filed Dec.

F 2 a QE 3m 8M. 6 N r A I .N EIJII-E w. M E A n .H O

Y 8 mm 6E Patented Oct. 18, 1949 UNITED STATES;

PRESELECTED STOP MEANS' FOR TUNER ELEMENTS Illinois Application December31, 1943. Serial No. 516,362

8 Claims. (Cl.'192143) This invention relates-to control devices and inparticular to devices for tuningradio-apparatus of the typethatis-efiective to tune radio apparatus manually or automatically.

It is desirable in a radio receiving or transmitting system to havecontrol apparatus of small size, of simpleconstruction and of a minimumnumber of. parts for changing the tuning ofthe system.- Theparts'comprisingtheapparatus are preferably such that they are. easilymanufactured and. assembled and easily adjusted to tune inapredetermined station, or easily varied to tune the system toany oneparticular frequency in. a given frequency band. Mechanical tuningdevices adapt themselveswell to these requirements and they arerelatively inexpensive to-manufacture for they donot require all' ofthe. costly elements such as switches, coilsand condensers used in mostelectrical-tuningschemes wherein onlya. limited number of the tuningstages of the radio apparatus are tuned due to space requirements orexpense.

In addition, it is desirable that the apparatus have. a control-memberwhich is readily accessible to an operator either for adjustingthe-apparatus whereby it is eifective either to tune in predeterminedstations automatically whena second control member. located at a. remotepoint is actuated, or for. varying the. tuning of the systemcontinuously through a given frequency band.

An object: ofthis inventionis to provide improvedapparatus fortuningradio apparatus.

A. further obj ectof. thisfinvention is to. provide novel controlapparatus for generaluse in a wide variety of electrical equipment,including laboratory apparatus, power generation apparatus, and motivepower equipment, as well'as tunabIeapparatus such asradio transmittersand receivers.

Still another object of the present invention is to provide improvedtuning apparatus especially adapted for use in compact radio equipmentsuch as marine, aircraft and automobile radio equipment.

A still further object of the present invention is to provide improvedmeans for enabling ready and convenient adjustment or variation of an.

electrical circuit controlling'element.

A still further object of the'present invention is to provide noveltuning apparatus of the mechanical type of small size in the manufactureof which accurate'machine work to close tolerances is not required, andwherein loose fitting parts and play between the parts of either willnotafiect accuracy of tuning.

Yet another object of'this invention-isto'provide-improved apparatusincludinga convenientmanual operating member for setting up thestations. in a broadcast receiver without requiring the use of aligninginstruments so that predetermined; stations are automatically tuned inwhen. pushbuttons orother similar apparatus is actuated; said manualoperating memberbeing arranged also'to tune the receiver continuouslythroughagiven frequency band. a 7 Still another object of this inventionis to provide an' improved radio tuning device for automatically ormanually-tuning'radio apparatus without much effort on the part of an:operator. The features of the present invention which are ,believed tobe novel are setforth-with particularity in the appended claims. Thisinventionitself, both'as toits organization and manner ofoperatiorrtogetherwith further objects and advantages thereof,.may bestbe understood by Fig. 5' is a sectional view taken substantially on line5-5 of Fig. 3;

Fig. 6 is a sectional View taken substantially on-lines 6.--6.of Fig. 3;

Figs. '7- to-10 show positionsof certain elements of theapparatus shownin. Fig. 1 in various operating positions;

Figs." 11 and 12 show respectively an elevational and-a sectional viewtaken substantially on lines ll--|'I and l-2'-I--2 of'Fig. 1;

Figs. 13- and 114- are sectional views taken substantiallyon-correspondinglines in Fig. 12;

Fig 15 shows a control circuit for apparatus embodying this inventionFigs: 16 and; 1H. show-.modified arrangements of theiapparatus shown inFig. 1

Figs. 18 and 19 show a portion of the indicating mechanism in apparatusembodying this invention;

Fig. 20 shows a modified indicating mechanism in apparatus: embodyingthe present invention; and

Figs. 21-24; inclusive, show modified apparatus embodying: the presentinvention.

This invention-has particular applicability'to a tuning: system of thetype in which an. electrical circuit controlling; element may either be3 conveniently positioned to predetermined positions and laterautomatically actuated to such predetermined positions to tune anelectrical circuit to predetermined frequencies from a remote point bymeans including a solenoid; or the circuit controlling element may bepositioned continuously over a range of positions from a point near thereceiver by manually operated means so that an electrical circuit iscontinuously tuned over a frequency band.

The tuning apparatus disclosed herein is broadly of the turret tunertype disclosed and claimed in United States Patent No. 2,310,720 ofClarence W. W andrey, sued February 9, 1943.

Referring to the drawings wherein the same reference numerals in all ofthe figures designate similar parts, Fig. 1 shows apparatus foradjusting or varying the position of each one of the powdered iron coresor slugs it (Fig. 13) with respect to associated inductance coils l2encased in and electrically insulated from metal cylinders l5 and 16,which cylinders are joined by a metallic web 11.

It is well known, of course, that the relative position of eachcylindrical core member or slug H! in its associated coaxial inductancecoil 12 determines the inductance in henries of that particular coil.When, as in this application, one of the inductance coils I2 isconnected in parallel circuit relationship with a condenser, therelative position of the core member and associated coil l2 determinesthe resonant frequency of the circuit formed by the inductance coil 12and the condenser. In this way, the position of the core member it] withrespect to its associated coil l2 determines the frequency to which aradio receiver or transmitter is tuned.

The apparatus disclosed herein is effective to position the core membersH) with respect to their associated coils such that those core membersassume predetermined positions with respect to their associated coils l2when the radio receiver or transmitter is automatically tuned byoperating a pushbutton or similar device. Furthermore, the apparatusdisclosed herein is effective to produce a continuous movement of thecore members 10 with respect to their associated coils '12 when it isdesired to tune the radio receiver or transmitter continuously through agiven frequency band.

In this particular arrangement of my apparatus, the core members [0 aremade movable and their associated coils l2 are relatively stationary,such coils being encased in and insulated from metal housings orshielding members l5 and l6,-which housings are suitably fastened tobase plate l8. It is understood, of course, that the coils 52 themselvesmay be made movable and the core members stationary, or the movable coremembers l0 shown herein may form one element of a cylindrical condenser.In its broadest aspect my invention has special applicability to anycontrol arrangement wherein it is desired to position one element withrespect to -a second element.

In Fig. 1, the core members it are preferably adjustably mounted oncarriage member 13 by means of a flexible coil sp ringlike member whichhas one end fastened in the core member !0 (Fig. 13) and is adjustablyheld in carriage It by the screw-threadlike portion of the spring member20 engaging a cooperating screw-threaded portion in carriage 19. Thisparticular man ner of adjustably mounting the flexible members 20 andcore 10 per se forms no part of this invention, but is disclosed andclaimed in the United States Patent No. 2,423,275 of Clarence W. Wandreyissued July 1, 1947, and assigned to the assignee of this invention.

The movable carriage 19 carries core members 19 and its positiondetermines the position of the core members H! in their associatedinductance coils l2, the carriage l9 being slidably mounted on guidemembers 22 and 23 (Figs. 1 and 2) which pass through cooperating guideapertures in the carriage l9. Carriage I9 is normally biased to theright in Fig. 1 against the most downwardly positioned one of theangular spaced stop members 25 by means of a prestressed spring 26having one of its ends 21 (Fig. 2) fastened to the carriage extension28, and its other end 29 fixed relative to the base plate I8 in baseplate hole 32. Carriage I9 is provided with a recessed portion 19!arranged to snugly receive a stop member 25 for increasing the resetaccuracy of carriage 19 in repeated operation of the tuning device.

Spring 26 is confined between the base plate l8 and a circular member30, the spring 26 be: ing wound and prestressed around the bolt 3| whichhasone end threaded in base plate I8, and which has circular member 30attached on its other end by means, for example, of a pressed fit. Theparticular spring 26 is used advantageously because it occupies a verylimited space and the force exerted thereby is relatively constant overthe length of the travel of carriage H! from abutting relationship withthe turret actuating member 33 in Fig. 4 to abutting relationship withthe most downward one of the stops 25 on turret 35 in Fig. 1.

Movement of carriage IE to the left in Fig. 1 on guides 22 and 23against the action of spring 26 to abutting relationship with turretactuating member 33 (Fig. 4) is accomplished by energizing solenoid 34(Figs. 12 and 14) disposed with its longitudinal axis parallel to andspaced midway between the extension of the axes of guide members 22 and23 (Fig. 2) such that when iron core 36 attached to carriage [9 by meansof screw 31 (Fig. 2) is attracted by the magnetic force set up by thesolenoid 34, carriage 19 moves to the left in Fig. 1 on guide members 22and 23 without much friction but against the action of spring 26.

As long as solenoid 34 is energized, carriage 19 remains in itsfurthermost left position in Fig. 1, but when solenoid 34 is deenergizedthe carriage l9 moves to the right on guides 22 and 23- under theinfluence of restoring spring 26 until carriage movement to the right isarrested by one of the stop members 25 on turret 35.

In the furthermost right position of carriage IS in Fig. 1, after itreturns from engagement with turret actuating member 33, another stopmember 25 is engaged which, of course, determines the rest position ofcarriage l9 and determines the position of core member H) in itsassociated inductance coil l2. The means for causing another stop member25 to arrest the travel of carriage I9 is described generally now and inmore detail later.

In general, when carriage I9 moves to the left in Fig. l and approachesthe end of its travel, it engages the turret actuating member 33 andthen moves it from its normal position shown in Fig. 3 to the positionshown in Fig. 4 during which movement the turret actuating mechanism 39is conditioned to rotate the turret shaft 40 and turret 35 an angulardistance corresponding to Kim anguiar distance; between; adjacent; stops253 turret; carriage" w moves from: its furthermost left. position nearthe position shown. in l lgz grdie tiirretzshatam and-i mechanicallyconnected turret is rotatedan. angular" distance to the angulandistance: between stops 2 5 amthati movement-of carriage-lime arrestedby as stop; adiaoent tor: the. one which previously arrested; 'theamovement. of carriage Ni Immg: I, the-turretzcarryingthe adj us-tabl'estops; 25 ancthavi'ng itsshaft extending substantiailythe=fi1llilengthat the composite device is journaled respectively in thevertically extendingg'anct. supportingplates 5% and 53 respectively at.points-5E and- 55, the'plate jz and 53 being Suitably secured to: thabase plate- #8 bymeans of-screw connections: shown in Figs: 7* and-'-I4.

shaft 60 isearranged to berotated intermittentiy'and. only'clocitwise inFig; 1' an angulandistance corresponding'to the angul'ar-distancebetween adjacent stops 25 each time carriage I-9 moves. to.it'sifurthermost left position in Figs. 1 and? returnssubstantiallytoits initial position:

Such intermittent movement of" turret shaft is causedby imparting;alternate clockwise and countercloclwise movementto gear 42in Fig. 6whiol'i-isrotatably'and slidably mountedon turret shaft 40, theclockwise and counterclockwise movement being substantially an angular"distance. corresponding totheangular distance betweemadjacent-stopszfiA= pawl-and ratchet en-- gogementbetween gea1-42 and shaft isprovidedifor causing turret shaft Ml tomove only in accordance withthecounterclockwise movement of'gear'fl inFi'gd Pawl teeth 45' on extensionii ofgear flf-are pitchedi'an' angular distance corresponding'totheangular'distance' between stops wandare normally pressed intoengagement. with cooperating" ratchet teeth H on turretshaft til'bycompression spring- 49 having one: of its-ends abutting the bodyportion of looking gear 5!) fixed on turret shaft 40 and. its other endabutting-ti'terotatably" and slidably'mount'ed gear 42.

when gear 42* is: moved clockwise in Fig, "6 relative'movement isproduced' between gear 42 andtnrretshaft llflpawkteethw'ride on ratchetteeth fland cause gear: 42 toslide to. the leftlin El'gr. at on shaftdfland" such relative, movement continuesuntil the pawl portion ofteeth 45,is

pressed into an' adjacent cooperating, notch of ratchet gear 4!by'compression spring It. In suchlatter'position gear #2 ispositionedito. 1:0.- tatetun'etishaftifl when gear 4'2fismdvedcounterclockwise, asu seen in Fig. 6f

Suitableclockwise andfcounterclockwi'se. movemenizrof; gear 42 forvintermittently turning turret iiisaproducedbylinear back and'forthmovement of "turret. actuating member. 33,, such back movement? being;produced by engagement of carriage lfwithmember- 33. as. shown in Fig..4. andsuch forth movementabeingproduced. by the. action. of restoring.spring, 5!? having one of its ends. connectediito. an extension. 51 of.member. 33; and. its other: end; fixedlrelativer to thebase. plate. it.on housing 5'42 Such back and; forth. movement of member 33 causesrespectively counterclockwise andfciockwise movement inFig. 6. of. gear.Solon cylinder filfthroughwhich the member 33 passes,andisincegear'fiwconstantiy engages gear 42 the 'movementpfi'gear*BUcauses corresponding move.- mcntofigeamfli For this purpose turretactuatingmember. 33 meme 3? suitable: carriage bearing face forengagement with carriage wand a twisted'por- 6 nom- 63 (Eggs: hand 6):arrange'dltoipassi through cylinder-6t and rotate gear-6.0 issupportiedtfon linear movement on' support; 54'; the supports-54 beingsuitably fastened: to the: supporting plate 531 by meansof? screws 56;.Thecylinden 64: is j ournaled? in; a. suitablyrecessed portion. of'support 54' withthe twistedi portion 6310f actuating member 33passin-grtherethrough and: a. suitable guide aperture: 64 in: support:54'. so?- that: downward movementrin ll ig. 4 of member 333 ancbgear B0is limited; upward movement; of cylindervfil in: Fig. 4' being limitedby the. engagement of gear" Ell with. gear." 42: and movement. ofcylinder 6a. along its" axial length being'limited: by: flanges 6t" andt?! on support-154.

Thus,. linear movement of actuating member istransformed into suitable Yrotary: movement of 'gear St and connected gear M'by: providingactuating member '33 with a suitably twisted: portion' 63% along its:axial length: and by: providing a suitablelcurved aperture in cylinder6a through which: twisted portion 63 passes in cooperating engagement.

Since the gear- 4? slides as well as rotates on its ;supporting'sha-ft:40;.the axial length-oi gear I 412 ismadesufi'iciently large andits=gear-teeth are-so: shaped that gear 6ll=remains= in constantengagement withgear 42 during a cycle ot'oper atifon corresponding toa-bacltzrand forth movement of actuating member" 3 3;

In order that: the turret 3-5" and its shaft 4E1 may-not rotatewhen theapparatus is inthe posi tion shown in Figs. 1 and 3; the turret shaft!is blocked against. clockwise and. countercloek wise rotationrespectivelyin Fig. 5- by flexible spring member Til (Fig; 5) fastenedtosupport E lby screw 12 and projection H carried-byworret actuatingmember the -end of spring member 10- and projection H'- engagingsuitable portions of the locking wheel 50fixed onturretshaft to. It isnoted that spring mis-positioned soas to; prevent at alltimes anysubstantial clock-'- wise movement in Fig. 5 0i turretshaft M and thatsubstantial" counterclockwisemovement of the turret shaft 4B ispermitted only when actuating: member 33 is displaced by carriage It inwhich latter case projection H does not" engage locking wheel" 50;

With theapparatus thus fardescribed" it is evident that, each timeactuating solenoid 3tis energized; the carriage l9 moves againsttheaction of spring 26-from engagement with onestop member 5- toabuttingand operating engagement with" turret actuating member 33' so as tocondition the turret actuating mechanism 39 for-rotating the" turret 35,and that when the actuating solenoid 34 is deenergized the carriage t9movesunderthe influence of restoring spring 26; the turret 35 revolvesan angular di'stancecorresponding to the angular distancebetweemadjacent stops 25 and further movement of the carriage is.arrested by an adjacent stop 25..

Each. stop member 25.'adj ustab1y mounted on individual screw-threadedshaft in a direction substantially parallel to the axis of inductancecoil I2 is displaced from adjacent stop members by equal angles of 60 inthe particular device shown. Rotation of screw-threaded shaft T5 causeslinear movement. of the associated stop member. carried thereon, theparticular. stop member 25 being guidedand held from rotating by thecooperation of stop extension 17 (Fig. 2) in turret shaft grooves 18.?extending the full length of adjustable stop travel;

Each screw=threaded stop positioning or bearing shaft 15 is journaled atits opposite ends in spaced flanges 80 and 8I (Fig. 1) fixed on turretshaft 40, the end of each such positioning shaft -I5 carrying a gear 83fixed thereto and arranged to be engaged by a gear of a manuallyoperated actuating mechanism to be described now for adjusting orvarying the position of a stop 25 on its associated screw-threaded shaft15.

A gear 83 fixed on each rotatably mounted shaft 15 is arranged to berotated by gear 90 on manually operated shaft 9I having a knob 92mounted thereon so that a stop 25 threaded on shaft I5 moves along theaxial direction of shaft I5 when knob 92 is rotated with gear 90 incooperating engagement with gear 83 as shown in Fig. 1. Gear 90 isarranged to engage that one of gears 83 which is in the lowest positionshown in Figs. 1 and 7 by moving the upper end of shaft 9I to the rightin Figs. 1 and "I about a pivot point substantially in the plane of topplate I42 and in a direction substantially perpendicular to the axis ofshaft 9| so that shaft 9L assumes the position shown in Fig. 9.

When shaft BI is moved from its position shown in Fig. '7 to theposition shown in Fig. 9 by such movement of the upper projecting end ofshaft 9| to the right in a direction substantially perpendicular to theaxis of the shaft, gear 90 cooperates with gear 83 so thatscrew-threaded shaft 15 is rotated by rotating knob 92. Such rotation ofscrew-threaded shaft I5, having ends of reduced diameters journaled inmembers 80 and 8|, causes longitudinal movement of that particular stop25 on that particular shaft I5 which is rotated by rotation of gear 90,

Manual control member 9| having a convenient knob 92 mounted thereon isarranged to be positioned not only to rotate one of the gears 83separately as shown in Fig. 9, but is also arranged to be automaticallydisengaged from such gears 83 as shown in Fig. 7. Control member BI ismounted with a reduced portion I40 snugly engaging a cooperatingaperture MI in the head plate I42, the head plate I42 being securelymounted to support member 52 by screws 58, and with a face I45 on member9I slidably mounted on the upper face of platform I48, which platform isnormally held in adjustable position on supporting member 52 by means ofscrews I41 and I48. In the adjustment of the platform I46 for suitablemovement of control member 9| to cause proper mesh between gears 83 and90, the screws I41 and I48 are loosened and the platform I46 is guidedby such screws and pins I49 and I59 in support 52 cooperating withapertured portions I5I and I52 of legs I53 and I54 of platform I46.

In order to hold manually operated shaft 9| in the position shown inFig. 9, a latch mechanism 95 (Figs. 8 and mounted on base plate I8 isprovided. The function of such latch mechanism 95 is to hold thedownwardly extending end of rotatably and pivotally mounted shaft 9| inits furthermost left position in Fig. 9 and to allow the manuallyoperated shaft 9| to assume its normal position shown in Fig. 7 whencarriage I9 is moved to the left in the direction of the arrow in Fig.9, such carriage movement being produced by energizing solenoid winding34 in a manner described previously.

Latch member 98 is pivotally mounted on base plate I8 by passing' ashaft 99 respectively through suitably apertured and spaced ears I00 and"II and suitably apertured and spaced ears I02 and I03 on base plate I8and member 98,

8 the shaft 99 being suitably held-in base late ears I00 and IN byenlarging or bending the ends of shaft 99.

Latch member 98 is normally biasedso as tend to rotate clockwise inFigs. 7 and 9 due to a prestressed coil spring I05 wound around shaft 99and having one of its ends I08 contacting member 98 and its other endI01 contacting base plate I8, such clockwise movement being limited bybifurcated integrally formed fingers H0 and III contacting base plate I8when manual control member 9| is in the position shown in Fig. 9.

In the normal position of the control member 9I shown in Figs. 1 and '7,the member 98 is prevented from assuming its furthermostcounterclockwise position in Fig. 7 by engagement of control memberhead- II4 with each of the bi:- furcated integrally formed arms H6 andII! of latch member 98. The bifurcated arms I18 and II! are separated byan enlarged opening I20 through which control member head II4 passeswhen it is moved to its furthermost left position in Fig. 9 against theaction of coil compression spring IZI, the coil spring beingprestressedby winding it around post I24 mounted on base plate I8 withone end I25 engaging control member shaft 9I and with its other end I26engaging a suitable opening in base plate I8.

Control member 9I in Fig, 9 is maintained in the position shown becauseas shown in Fig. 10, its head H4 is positioned in the cooperatingopening I20 of latch member 98 and latched in that position. Head H4 isunlatched by rotating latching member 98 counterclockwise in Fig. 9about its supporting shaft 99 in which case the cylindrical walls ofhead II.4 frictionally engage the cylindrical walls defining opening I20until the member 98 rotates to a point where the smaller reduceddiameter portion I30 of control member 9I enters opening I20 at whichpoint control rod BI is pushed to the right in Fig. 9

by spring I2I.

Such counterclockwise movement of latching member 98 for unlatchingcontrol member head II4 results from movement of carriage I9 in thedirection of the arrow shown in Fig. 9. For that purpose, integrallyformed finger I3I on pivotally mounted latch member 98 normally extendsup above the plate I8 and out of the path of motion of carriage I9 asshown in Fig. 7, but after control member 9| is moved to the right inFig. '7 so as to assume the position shown in Fig. 9, the latch membernot only maintains the control member 9I in the position shown in Fig. 9but also the latch member finger I3I extends up into the path of thecarriage I9.

When carriage I9 moves to the left in Fig. 9 in the direction of thearrow, the finger I3I is cammed downwardly and the integrally formedbifurcated members H6 and III defining enlarged opening I20 are movedupward to a position where the reduced diameter portion I30 of controlmember shaft 9I is allowed to move to the right in the space I35 definedby the spaced bifurcated members H6 and H1 under the influence of springI2 I.

Carriage I9 is moved to the left in Fig. 9 when solenoid winding 34 isenergized and when so moved trips the latching mechanism 95 when and ifsuch latching mechanism is effective to maintain gears and 83 incooperating engagement with one another.

The details of the variable inductance construction are shown in Fig.13. Inductance coil supported structure includingcoil -I2 -.inthe.cylin- Iier d5. -Thebther-endoi insulating cylinder I63 issupp'orted'byran-insulating washer 166 in cylinder i5. .:A.-magnetic.flux-path isprovided for-the flu-x set up in coil 12 by providing -a powdered iron=cylinder -I6I coaxiallydisposed with respect to coil 1:2 and byiproviding the relatively movable {powdered iron cylinder II] which ispositioned in coil I2 in a manner described above. The core rmember IIIis guided in its movement inlthe insulating-coil support I63 and theother powdered iron imember II5I snugly engages the inner cylindricalwallsof shielding and supporting member -I'5 and is prevented frommoving axialLyIby-fengagementwith washer I66 and closurezmember 164.Member I5 is fastened tobase plate 1.8 bymeans-ofscrews I'IIJ '.(Fig.11).

.The details :of the 'magnetic means for moving carriage t9 are shown inFig. 14. The solenoid 34 having terminals I! and N2 -(liiig. 11) iswound on an insulating cylinder I13 which is supported 5011 base plate48 :between supporting members 53 and 21:75. '(Jylincler I13 has one endfixed Lin a cooperating :aperture in supportingonembertfiseazmiritszotherend fixed ina cooperating aperture ininsulating member 116. 'Axial movement of cylinder I13 is prevented bysuppoiitingfmembers flzand i :15 fastened to base .plate +8 -by means offastening screws H8 and I19. Solenoid core member 36 attached tocarriage I9 by means of screw fli'l is drawn :into ."solenoi'd winning1'34 when current flows "through "winding 34 for actuating the oarriageI9 in a :manner describedrabove. Movement of core 36 endearriage I9 tothe left in Fig. 14 isaccomplished @by energizing winding 34, andmovement of core member 36and carriage 1| 9 to the right-in Fig. 14after winding 534 is deenergized is accomplished :hytthe prestress'ed'sprin'g having its end 2.! fastened to carriage extension '28 which is.held on carriage 19 by means ofscrew IBI.

'15 shows a oircuit:arrangementfior eneragizing solenoid winding 34 formoving core 36 and carriage ill! to 'theileft in Fig. 14. 'In Fig-1'5,one of the terminals IaII of solenoid winding 34 is connected to thepositive terminal of :a'voltage 1 :source I82 and "the other terminal1:12 is connected ztoone terminal of switch I85 which may, fior example,be a footswitch :of the type shown inEPatent No. 2,216;6'71lofIMcDonald,the -remainingterminal of switch IRS-being connectedto the 60 negativeterminal of source 182 which maybe 'the storage battery in anautomobile.

Under very exceptional conditions, in the arrangement shown in Fig. '1,the=carriage I9 may *move to the right beyond a particular stop mem-Fber arranged to limit such movement of carri'a'ge I9 when the turretmember is rotated. This is so since, under :"certain exceptionalconditions, the carriage I9 may move independently of the position ofturret :member 35. In order te tament-such abnormal movement of carriage$9, .the twisted longitudmally movable actuating member 33 shown .inFig. .16 is permanently eonnected-tocarria'ge I9.

1111 .Fig. 16, actuating member -33 rhaving the it twisted portion .63arranged to'rotate gear (Fig. .6) is permanently fastened to thecarriage l9 =-at point 490. The recessed portion I9I o'f oarrriagel'llisarrangedto snuglyreceive the most downwardly extending one of therectangularly shapedstop members 25 (Fig. 1) in its mostright position.in Fig. 1. With this arrangement in Fig. 16in which the actuatingmember .33 is connected to carriage I9 and actuating member 33 isoperatively connected to gear 6b as shown in Fig. 5, Jit'is clear thatthe turret'35 and carriage L9 are always mechanically connected togetherand thaltthese members are not allowed .to move independently of oneanother but move jointly.

-Inthe arrangement shown in Fig. 16, a .restoringspringisnot connectedto member-33 as shown in .therarrangement of Figs. i3-and 4, but thesame purpose .of restoring carriage I'll and member 33 tonormaloperatingposition is providedby prestressed coil spring 359 having oneof its ends attached to carriage I9 and the other end attached tosupporting member 53. Buffer coil springs35 I and.352.-mountedirespectively ongui'de members 2.2 "and 23 and having oneof their ends attached .tosupporting member 53-and the other one oftheir .ends free for movement by carriage I egprovidesanadded force forreturning the carriage is to the right in Fig. .16 after it is moved .tothe left .in Fig. 16 by .magnetio attraction of magnet core member .36.'Itis noted that bufier springs '351 and=35-2 are compressed only whenthe corezmember "36 is sufiicientlyfar within its actuatinglsolenoid 34(Fig. 14) that relatively large .forcesareav-ailable .formoving carriageI 9. Conversely, the magnetic .field set up in solenoid 34 (-Fig. .14)when'used in the-arrangements'hown .in Fig. 16 need beof relativelysmall magnitude for effecting .a cycle of operation. That is, buffersprings .35I and 35z andspring 350 may be con- .sidered to be a compoundspring whose .action allows aminimumamountof magnetic actuating .force.

:Also,.-in .the varrangementshown in Fig. 16, it .is noted that theposition of the axis of coil spring .351! ohanges during a cycle ofoperation of :the turret tuner. That is, coil spring 350 is .free tomove within-a space bounded by the-bent .metal strap 355 which isrigidly mounted on base plate 48. With this particular arrangement ofcoil spring 350, the .force exerted by spring 350 on carriageeduringa-cycle of operation of the carrriage -!I.9 is relatively constant.

Fig. 17 shows an arrangement for allowingpassage --of a stop [member 25past the carriage I9 when, under exceptional conditions of :operation ofthe arrangement-shown'in Fig. -l, the .car- .riage I9 moves =.to theright in Fig. 1 beyond the point at which such stop "member 25 normallyarrests motion of the carriage. Such exceptional conditions arise whenfor one reason or other the carriage i9 is 'moved independently ofthemosition of turret .35.

.In Fig. 17, the carriage i9 hasa spring biased stop-enga'ging memberI32 pivotally mounted'on .shaft I93 which has its o posite ends fixed inoppositely disposed faces I94 and I95 of carriage 49. :Member 192 :isnormally biased against ithe projections Ififi and i-fi'l-of carriagelil'byspring 2M having one of its ends fixed tothe fixed-shaft .493 andhaving its other end 201 abutting the normal .ston engaging face 203. Innormalopera- 'ti'on, member I92 is'spring 'biased against projections I95 and I9! and movement of carriage I9 islimited bycontaot-of a stopmember 2-5 against theiace 03 of member IiB-Z. However, when,

'11 under abnormal conditions, the carriage I9 is moved past itsparticular arresting stop 25 under the influence of spring 26 (Fig. 1),and when subsequently solenoid 34 (Fig. 14) is energized,

carriage I9 moves, member I92 is deflected downwardly due to contactbetween member I92 and a stop member 25, and such stop member 25 clearsbetween the oppositely spaced faces I96 and I91 of carriage I9.

The position of core member I9 and connected carriage I9 is indicated bythe angular position of gear wheel 229 (Figures 11 and 12) on shaft 22Iwhich is operably connected to carriage I9. A gear train (not shown) maybe connected to gear 229 for transmitting its angular position to aremote point by suitable and wellknown indicating mechanisms, or, in themodification shown in Fig. 20, the shaft 22I may be directly connectedto an indicating pointer 224 arranged to cooperate with an indicatingscale 225 on an extension 225 of top plate I42, top plate I42 beingfastened by means of screws as shown in Fig. 1 to the supporting members52, 53 and I15.

The mechanism for transferring linear movement of carriage I9 carryingcore members I9 to rotary movement of shaft 22I carrying gear wheel 229-and an indicating pointer 224 (Fig. 20) is described now.

Carriage I9 is joined to a linearly movable and slidably mounted member239 having a pair of tongue members 23I and 232 (Fig. 18) slidablyengaging grooves 235 and 235 in the modified tuning coil holder andshielding structure IA. In the assembly of the mechanism, the slidablemember 239 is joined to carriage I9 by inserting the tongue members 23Iand 232 in their cooperating grooves 235 and 236 in member I5A and thenbending member 239 within its resilient limits such that oppositelydisposed projections 231 and recessed portions 239 and 249 of member 239when member 239 is allowed to assume its nonbended or normalconfiguration as shown in Fig. 18.

Slidable member 239 carries a pair of projecting portions 242 and 243,projecting portion 242 serving as an abutment for anchoring tensionspring 248 and projecting portion 243 serving as a contact face forcylindrical member 249 on arm 259, which member 249 moves on the surface25I of member 243 but which positively engages member 243 due to theforce exerted by tension spring 248 having one of its ends anchored onprojection 242 and its other end fastened to cylindrical member 249 onarm 259.

Lever arm 259 connected at one of its ends to shaft 22I and connected tospring biased cylindrical member 249 at its other and transforms linearmovement of projection 243 On member 238 to rotary movement of shaft 22Iand gear 229 so that the angular position of shaft 22I and the positionof parts connected thereto serve as an indication of the position oftuning members I9 and the tuned condition of a radio receiver in whichthe coils I2 and core members I9 form a part.

Figs. 21-24, inclusive, show a modified manual control means arranged toposition stops 2.5 on their threaded shafts 15. This modification ischaracterized by the fact that the manual control rod instead of movingpivotally, as in the prior arrangement, moves in a directionperpendicular to its axis.

In Figs. 21-24, inclusive, rod 215 having actuating ear 216 integrallyformed thereon and mov- 238 on carriage I9 operatively engage able in adirection parallel to its axis in cylindrical guide openings 218 and219, respectively, in the top plate I92 base plate I8 and supportingmember 52 is normally biased downward in Fig. 21 by prestressedcompression spring 289 with shoulder 28f of rod 215 in engagement withthe curved extension of supporting plate 52, the'spring 289 having oneof its ends abutting top plate 218 and its other end abutting theshoulder 283 having gear 216 thereon.

When manual control rod 215 is moved upward in the direction of thearrow in Fig. 21, gear 218 engages the most downward one of the ars 93on its associated rod 15 so that a stop member 25 carried on such rod ismoved along the rod 15 by rotating manual control rod 215 with gear 216in engagement with gear 83. Rod 215 is maintained in its engagingposition with gear 83 by a latch mechanism 285 described now.

lhe latch mechanism 285 for holding gear 216 in engagement with gear 83comprises a latch bar 288 slidably mounted and guided on base plate ISwith a spring 281 for biasing the end 299 of bar 286 into engagementwith the projecting end of manual control rod 215, the compressionspring 281 having one of its ends abutting a recessed portion of baseplate I8 and its other end abutting the recessed portion in bar 286 soas to tend to push bar 286 to the right in Fig. 21.

The bar 286 is slidably mounted and guided on base plate I8 by pins 292and 293 respectively passing through latch bar apertures 294 and 295 andhaving one of their ends anchored in base plate 18, the other ends ofpins 292 and 293 carrying enlarged heads 296 and 291 for holding latchbar 286 on base plate I8. A projecting portion 299 of latch bar 286extends gupward through an aperture 399 in base plate I8 in the path ofcarriage I9 for moving latch bar.

286 to the left in Fig. 21 each time solenoid 34 (Figs. 12 and 15) isenergized whereby end 299 of latch bar 286 disengages the manual controlrod 215.

Manual control rod 215 is latched into operative position with one ofthe gears 83 (Fig. 21) by moving it upward in a direction parallel toits axis in which case the spring pressed latch bar 286 having openin395 of slightly larger diameter than the diameter of control rod portion391 engages such portion and enlarged portion 398 as shown in Fig. 24 soas to hold the manual control rod 215 in its most upward position inFig. 21 in engagement with gear 83 and against the action of compressionsprin 289. Then, when carriage I9 is moved to its furthermost leftposition in Fig. 21 by energizing solenoid winding 34 (Figs. 12 and 15),carriage I9 abuts-latch bar projection 299 and moves the latch bar end299 out of engagement with the reduced portion 391 whereupon the manualcontrol rod 215 moves downward in Fig. 24 due to the action ofcompression spring 289. When and as carriage I9 moves from itsfurthermost left position in Fig. 21, latch bar end 299 engages theenlarged portion 398 of manual control rod 215 and movement of latch bar286 is thereby limited, such movement of latch bar end 299 being due tothe action of compression spring 281.

Referring again to Fig. 16, the carriage I9 arranged to carry themovable tuning elements of a radio receiver carries a pointer 499permanently fastened together for cooperation with a suitable scale 49Ion base plate I8 so that an observer may observe the tuned condition ofthe receiver.

massa e entinvention havebeenshown and described, it

will be obvious to those skilled in the art that changes andmodifications may 'be made without edeparting ircm, the invention in itschroader raspects, and therefore the aim the (appended claims is tocover all such changes and modifications as fall 'within the true spiritand scope of this invention.

I claim:

1. A tuner for a radio receiver comprising a :movable tuning member, acarriage for the tuning member, an adjustable stop .for "said carriage,a spring biased stop contact member pivotally rmourrted on the carriage,means ztending ato.move the carriage in one direction, means to iretractthe carriage in the opposite-direction, and means :operativelyconnectedto said first named means for positioning said stop .memberiin the pathof movement -.of said tuning member when said :retracting means movessaid tuning member.

2. FA tuner ,for .a radio receiver comprising a longitudinally movabletuning member and a series of stops, a carriage for the tuning member, aspring biased stop contact member pivotally mounted on the carriage, andelectrically operated means for rendering said stops efiective insuccession to arrest repeated movement of said movable tuning memberupon movement thereof in one direction.

3. In combination in a radio tuner, movable tuning mechanism, a.plurality of stops arranged to be sequentially positioned in the path oftravel of said movable tuning mechanism, a manual control, meansresponsive to movement of said manual control for operatively connectingsaid control to any one of said stops in engagement with said tuningmechanism, means responsive to additional movement of said control foradjusting such engaged stop thereby to adjust said movable tuningmechanism, and separate means for releasing said tuning mechanism froman engaged stop, for moving an adjacent stop into said path of travel,for moving said tunin mechanism into engagement with said adjacent stopand for disconnecting said control from such previously engaged stop andfrom said adjacent stop, said i disconnecting means being arranged tocause such disconnection between any one of said plurality of stops andsaid control as said stops sequentially engage said mechanism.

4. In combination in a radio tuner, movable tuning mechanism, aplurality of stops arranged to be sequentially positioned in the path oftravel of said movable tuning mechanism, stop moving means associatedwith each of said stops, a manual control, means responsive to sidewisemovement of said manual control for operatively connecting said controlto any one of said stops in engagement with said tuning mechanism andfor adjusting such engaged stop and movable tuning mechanism in responseto rotation of said control, and separate means for releasing saidtuning mechanism from a stop, for moving an adjacent stop into said pathof travel, for moving said tuning mechanism into engagement with saidadjacent stop and for disconnecting said control from such previouslyengaged stop and from said adjacent stop, said disconnecting means beingarranged to cause such disconnection between any one of said pluralityof stops and said control as said stops sequentially engage saidmechanism.

:5. In combinaiioniin aradio tuner, :a movable tuning member, arpluralitylof stops arrangeduro be sequentially positioned inthepathmfitrawel of "said movable rtuning member, said member and stopsbeing arranged to :be moved rintoccontact in only one "direction, :means"for :releasing zengagement 7 between said stop's :and member innesponse to movement therebetweeniin the opposite direction, a manualcontrol, means mesponsive to movement of said manual controlforfloperatively connecting said control to "any one-of said stops inengagement with said tuning :member, means responsive to additionalmovement of said control for *adjus'tingsuch engaged stop thereby"toadjust said movable tuning member, and separate means for movingsaid-member in said upposite direction away from a stop; 'for moving 'anadjacent stop intosaid path of travel, formoving said tuning member insaid one direction into engagement w'ithsaid adjacent stop and fordisconnecting said control from such previously engaged 'stop and fromsaid adjacent 'stop ;-"said disconnecting means being arranged to 'causesuch disconnection between anyone of "said plureality of stops and saidcontrol "as said steps so- 'quentially engage said "tuning member.

6. In combination in a radio tuner, a longitudinally movable tuningmember, a plurality of stops sequentially rotatable into the path oftravel of said tuning member, a gear having a hollow portion, a helicalmember movable longitudinally and arranged to pass through the hollowportion of said gear to turn said gear in response to longitudinalmotion of said helical member, means for moving said helical memberlongitudinally in response to at least a portion of the movement of saidtuning member thereby to turn said gear, a second gear engaging saidfirst gear to turn therewith, a pawl and ratchet arranged with saidsecond gear and said stops to rotate said stops in response tolongitudinal motion of said helical member an amount 'sufiicient toplace an adjacent stop in the path of travel of said tuning member, amanual control, means responsive to movement of said manual control foroperatively connecting said control to any one of said stops inengagement with said tuning member, means responsive to additionalmovement of said control for adjusting such engaged stop thereby toadjust said tuning member, and separate means for moving said tuningmember from a stop and back to an adjacent stop and for simultaneouslydisconnecting said control from such previously engaged stop and fromsaid adjacent stop, said disconnecting means being arranged to causesuch disconnection between any one of said stops and said control assaid stops sequentially engage said tuning member.

7. In combination in a radio tuner, a movable tuning member, a pluralityof stops arranged to be sequentially moved into the path of travel ofsaid member, means for moving said member in one direction awa from oneof said stops with which said member is engaged, spring means for movingsaid member back into engagement with.

one of said stops, and means responsive to such back movement of saidmember toward said stops for moving previously engaged stop out of thepath of travel of said member and for moving said adjacent stop out ofthe path of travel, said stop moving means being arranged to move saidstops during the initial portion of such back movement of said membertoward said stops whereby said stop moving means imposes substantialload on said spring means during such initial back movement, said springmeans comprising a relatively weak spring portion of sllfil cientstrength to move said member in the absence of said stop moving meansand a relatively strong spring portion arranged to supply sufficientadditional force to said member during such initial back movement tooperate said stop moving means.

8. In combination in a. radio tuner, a longitudinally movable tuningmember, a plurality of stops sequentially movable into the path oftravel of said tuning member, arotatable memher having a hollow portion,a helical member connected with said longitudinally movable tuningmember for longitudinal movement therewith. and arranged to pass throughthe hollow portion of said rotatable member to turn said rotatablemember in response to longitudinal motion of said tuning member andsaid. helical member, and means for moving said tuning member away froman engaged one of said stops and for moving an adjacent stop into saidpath of travel in response to rotation of said rotatable member and formoving said tuning memher back into engagement with said adjacent stop,whereby connection between said helical member and said tuning memberprovides movement of said stops only upon disengagement of said tuningmember and said stops.

OTTO E. WAGENKNECHT.

REFERENCES CITED The following references are of record in the file ofthis patent:

Fichter et al Feb. 29,

